1.5.3 Licences to ring or mark bats for scientific purposes These licences are only granted for research projects with clear objectives. Techniques such as fur clipping or the attachment of radio transmitters or passive integrated transponder (PIT) tags are also covered by these licences. Ringing and marking, or the disturbance associated with these activities, can be harmful to bats so that ringing has been stopped or severely curtailed in several countries. In the UK, the value of ringing and marking techniques is recognised, but licences are issued only for clearly defined projects which will be subject to the approval of the licensing authority. Details of approved ringing and marking methods are given in Chapter 6.